


Mistakes Will Be Made

by 23fayk



Category: Supernatural RPF
Genre: Alpha Castiel (Supernatural), Alpha Castiel/Omega Dean Winchester, Alpha/Beta/Omega Dynamics, Alternate Universe - High School, M/M, Mating Cycles/In Heat, Mpreg, Omega Dean Winchester, Pregnant Dean Winchester
Language: English
Status: In-Progress
Published: 2020-04-21
Updated: 2020-04-21
Packaged: 2021-03-01 23:07:08
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,008
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23765080
Author URL: https://archiveofourown.org/users/23fayk/pseuds/23fayk
Summary: Dean woke up slowly to the feeling of extreme heat and wetness underneath him. With his eyes still closed, he groaned trying to decide if it was sweat or piss. His eyes shot open and he sat up quickly when he finally realized what was happening. That wasn’t sweat between his legs, it was slick. He’s an omega, and he just went into heat.
Relationships: Castiel/Dean Winchester, Charlie Bradbury/Jo Harvelle
Comments: 3
Kudos: 55





	Mistakes Will Be Made

**Author's Note:**

> Hi everyone!! This is my first fic with more than one chapter so please leave constructive criticisms in the comments!

Dean woke up slowly to the feeling of extreme heat and wetness underneath him. With his eyes still closed, he groaned trying to decide if it was sweat or piss. His eyes shot open and he sat up quickly when he finally realized what was happening. That wasn’t sweat between his legs, it was slick. He’s an omega and he just went into heat.

He slowly got out of his bed while he felt shame and disappointment deep into him. What would everyone think, they all thought he’d be a big strong alpha. He’s tall and has broad muscular shoulders, along with confidence and charm only an alpha could have. Or so he thought. Then his thoughts drifted to Cas, his best friend. 

In some deep down space in himself Dean felt immense joy. Cas had presented as an alpha just a couple weeks ago. Dean had been devastated when he found out, assuming he would be and alpha he had wanted so desperately for Cas to be an omega so they could be together. But now, Dean was just utterly confused and he didn’t even know if Cas wanted him the way Dean longed for. 

Dean changed his boxers and slowly made his way up the stairs from where his room is in the basement to get some food and water. He prayed to every God he could think of that no one would be awake yet so he could keep this to himself a little longer. But because life hates him he smells bacon cooking as he nears the top of the stairs, which is not something he usually complains about.

He slowly opens the door and when his mother turns around to greet him she freezes, smile dropping from her face. Dean’s face burns with embarrassment until his mother stops just standing there and rushes over to pull him into a deathly tight hug. “It’s ok Dean, I’m gonna get you all set up with everything you need,” Mary whispered in his ear as Dean started crying, tears falling onto heated skin. “It’s not fair,” Dean sobbed into his mother’s shoulder as she stroked his hair. Once he had calmed down he sat on the couch while Mary gathered everything Dean would need through this time of pure torture from the store. He could already feel it getting worse, but what made it 10,000 times worse was when Cas walked in the front door like he does every day. Dean was frozen in his spot as he saw Cas stop mid greeting staring at him and flaring his nostrils breathing in the scent of omega in heat. Slick rushed out of Dean’s hole and he whimpered as Cas took a step forward. Dean couldn’t handle it, he got up from the couch and all but jumped on Cas and the boy caught him in his arms. “Cas please I need you so bad, I need your fat knot filling me up making me nice and full,” Dean nearly cried as more slick leaked out. Cas finally seemed to realize what was happening,”Dean that’s just the heat talking, you don’t really want me like that.” Despite what he was saying Dean could feel the solid line of hard alpha cock on his ass as Cas held him up in his arms. “That’s not true alpha, I’ve wanted you for so long, I wanted you since the first time I saw you under the big oak tree reading that one book,”Dean stuttered desperately, and needy. He looked in Cas’ eyes and saw the moment he broke. Cas finally pulled Dean into a rough heated kiss all teeth and tongue. After they somehow made it to Dean’s room with out killing themselves on the stairs, Cas all but threw Dean on the bed. Cas stripped himself as Dean watched in wonder. He knew his best friend was hot, but he hadn’t realized how much being an alpha changed him. His shoulders were wider, his facial hair grew more quickly, he was a bit taller, and once Cas was naked Dean realized he had a huge dick. After undressing himself, Cas made his way over to Dean and slowly removed his t-shirt and boxers, kissing all of the newly revealed skin. Dean just sat there and begged, “please Cas, need you so bad. I need to feel your knot in me filling me with pups.” Cas growled at the words possessively and slowly pushed a finger in Dean’s tight wet heat. Dean moaned and arched his back in pure bliss as Cas worked him open with carful movements. “Please I need more,” Dean whimpered and Cas eagerly agreed slipping another finger in and scissoring him. “You smell so incredible Dean, I want to taste you so bad please can I,” Cas asks almost whining with want. Dean nods his head and then nearly explodes when Cas licks at his tight heat overflowing with slick. “Please Cas please knot me I’m ready please!,” Dean nearly cried. Finally he feels the tip of Cas’ knot at his hole triggering a wave of slick. He slides in Dean slowly and gentle, like he’s afraid Dean will break. They both moan loudly once Cas is fully seated in Dean’s tight ass. Cas thrusts a bit unrhythmic at first, but thankfully for Dean he’s a quick learner. “Harder please, oh god yess please Cas,” Dean Moans softly in Cas’ ear. They kiss again, but sweeter this time and less heated. Dean moans loudly when Cas hits the spot that almost makes him see white. “Oh god right there Cas, please I’m so close,” Dean said as he moaned in between. Cas hit his prostate repeatedly, and soon Dean was shouting his pleasure and came untouched. Cas’ knot finally caught and he spilled deep inside of Dean with a grunt, and Dean comes again at the feeling. While locked together by Cas’ knot after catching their breath, they just stare at each other wondering what the hell they just got themselves into.


End file.
